docs: def closer_than(self, mesh, radius):
          """
          Check for proximity of points in the ``mesh``.
  
          :param mesh:
              :class:`openquake.hazardlib.geo.mesh.Mesh` instance.
          :param radius:
              Proximity measure in km.
          :returns:
              Numpy array of boolean values in the same shape as the mesh
              coordinate arrays with ``True`` on indexes of points that
              are not further than ``radius`` km from this point. Function
              :func:`~openquake.hazardlib.geo.geodetic.distance` is used to
              calculate distances to points of the mesh. Points of the mesh that
              lie exactly ``radius`` km away from this point also have
              ``True`` in their indices.
          """
          dists = geodetic.distance(self.longitude, self.latitude, self.depth,
                                    mesh.lons, mesh.lats,
                                    0 if mesh.depths is None else mesh.depths)
          return dists <= radius